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orly_andico

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Everything posted by orly_andico

  1. OnStep will work even with a tangent arm. But you have to push the scope to the "general" area and then it can do a short GoTo using the limited travel on the tangent arm. It would need to know where it is when you push it there though - which means doing a plate solve and then sync'ing the mount to the plate-solved position. Also: my personal experience, 5-phase steppers are a complete pain. You do need some really exotic drivers which are impossible to find inexpensively.
  2. The 8" Cassegrain as in this one? https://www.firstlightoptics.com/telescopes-in-stock/stellalyra-8-f12-m-lrs-classical-cassegrain-telescope-ota.html That does seem too much for an EQ-5. It is almost the same weight as the Mewlon-210 (8.1 kg) and slightly longer focal ratio. I can say from personal experience that the Mewlon-210 is under-mounted on the Takahashi 90S, which is larger than an EQ-5 (or Takahashi equivalent, EM-10 / EM-11) but smaller than the EM-200 (EQ-6 equivalent).
  3. OnStep didn't exist when I did that 600E goto conversion.. ended up buying an expensive (over 500 euro) German GoTo controller which is now defunct because the developer stopped working on it. The huge advantage of OnStep is that it's open source. There are a lot of PCB's floating around but the simplest possible implementation can be an ESP32-based Uno clone with two DRV8825 or TMC2xxx Pololu-style stepper drivers. BTW I used to have an Ender-3 3D printer with DRV8825 drivers, and I upgraded the motherboard to one using SilentStepStick (TMC2xxx) and it was night and day. Amazing. Stepper motors driven by TMC2xxx are even quieter than servos. Here's one of the canned/pre-stuffed OnStep boards that I bought from George Cushing on the OnStep forum. I've not actually powered it up.. (the AP600 is off somewhere, and I have two perfectly serviceable GoTo mounts): So below you see the ESP-32 is the OnStep brains (Arduino replacement), the small board at the top right is the WeMos D1 (ESP8266) which provides the Wifi, the two Pololu-style stepper drivers, there's also a Dallas chip for the RTC on the main board. I'm not quite sure why the separate WeMos D1 is needed, since the ESP32 itself has WiFi and Bluetooth. I think to avoid over-complicating the code.
  4. There's actually another aspect to this. Even if you have the big mount, it comes with correspondingly onerous setup times. Unless you can leave it set up all the time.
  5. EDIT: I just noticed the OP already has a C6. That would be my vote for ideal planetary scope on an EQ5. Add (expensive) Hyperstar and you've also got a good deep sky OTA. I had a Vixen GP and a C9.25 at one time. Not a good combo. I think a C8 is the maximum you'd want to put. Or maybe a 127mm Mak. Neither of these options is great for DSO, however - although there are pretty aggressive reducers for the C8 from the likes of Starizona. Of course with the C8 there also is the option of Hyperstar. The C6 is another option, and that can also take Hyperstar AFAIK. I also had experience with an 8" f/4 Newtonian. I wouldn't put that on anything less than an EQ6.
  6. 1) You should be looking at OnStep - all the hard work has been done by Howard and the team, a complete build can be done under $200, maybe even under $100. 2) The Meade 826/856 may not have a full declination worm, only a tangent arm. You'll need to check on this as GoTo range will be severely limited if so, as the DEC would not be able to be driven a full 360 degrees.
  7. Jupiter 2 hours ago. The mount is an ancient Takahashi 90S which is overloaded with this payload, but it's what was handy because I keep it on the balcony under a tarp. I literally just plug it into a power bank (modded it to run off USB) and off we go. The mount is also grossly unbalanced - there really should be more weights on the CW shaft, but I don't have any more large 18mm bore counterweights. Observing was OK, not great - even with glasses my eyes have different correction (much, much worse without glasses) and my binoviewers don't have individual focus.... (and yes, no finder.. neglected to put it on, so just eyeballed Jupiter using the knobs on the tube rings as "iron sights").
  8. Right after replacing the Renata battery in the handset and reflashing the database. See also the 3D-printed adapter to securely attach the Contax RA finder to the PASILL4.. I thought the Celestron tripod was a good idea (for unknown reasons, Celestron tripods have holes in the tops that are compatible with the ADATRI) but it isn't. I will not be repeating this stunt on those 1.5" steel legs in the future.
  9. https://www.ebay.co.uk/itm/166363489398 I really "need" more mounts/scopes like a hole in the head.. but this is an incredible bargain! The mount alone (which is a Vixen Polaris) is worth more than the asking price, it has the nice wooden legs, and the Celestron C4.5 newtonian (which is a 4.5" f/8 actually made by Vixen) is also worth more than the asking price IMHO. I've had two of the Vixen Polaris, and they are very nice, with a DIY motor drive or a modified Orion EQ-1M you can use them for basic astrophotography (and they have setting circles, which IMHO makes them superior to say the Star Adventurer). And it's not too far away.. a 90-mile drive for me. But maybe someone closer would want to get it...
  10. I got the Renata batteries from AllBatteries with the tabs already spot-welded to the batteries (interestingly the battery in my handpad was not a Renata, and not made in Switzerland). I desoldered the pigtail from the existing battery and soldered it to the new battery, and also replaced the heat shrink tubing for good measure. As my spool of solder is currently missing in action, I had to use the remnant solder on the pigtail ends to attach the pigtail to the new battery. The result wasn’t great - I prefer secure solder joints with a strong mechanical connection - but it seems fine. The new heat shrink provides an extra level of mechanical stability. Now to reflash the database…
  11. As an update: I got my order from AllBatteries today, Nov 6 (order made on Oct 27). Six working days. Now to replace the battery and reflash the database.. not looking forward to it.
  12. Incidentally, George also sent me the spec for the connector itself. It is a Belden 51021-0400 Picoblade, which you can buy from Farnell etc. however without the wires... the crimp terminals are Molex 50079-8000
  13. Thank you all for the extensive discussion. I ordered a couple from allbatteries - let's see where that goes. My challenge really was bonding the wires to the cell, that normally requires a spot welder (the cell is stainless steel and solder won't stick to it). But since there's tagged cells, it should be trivial to transfer the pigtail to the new tagged cell. Now if only I could find that pigtail as well... then I wouldn't need to desolder. But it's hard to say from Geof's photo. It appears to be a 4-pin mini Berg (?) with 2 missing pins. Probably for keying. Anyway transferring the pigtail is trivial. The AP handpad is a 15-20 year old "wonder" of engineering. The keypad backlight is a fat bundle of fibre optic strands that go from the PCB to the keypad. And when replacing that battery, you have to avoid folding or crushing those fibre optic strands. Just an extra headache. Then again, rumor has it the entire AP electronics package was outsourced to some military supplier. It certainly looks the part. Also telling that the new GTO CP4 controller with WiFi... implements the WiFi using a WiFi to serial bridge, it's the same old serial interface underneath.
  14. I did read that page before posting here... and came away understanding less than before reading the page. So much of the documentation presupposes that you know things already, e.g. how to get an export relief declaration; how to file an export declaration; etc. Lots of fun for the small business owner, less fun for me.. I may go down the desolder the pigtail route; or, if George can give me the part number of the pigtail and battery, make up a new set myself.
  15. Thanks Geof. I'm not traveling to the US anytime soon. I did think about de-soldering the pigtail and putting it on a new battery as a last resort. That option just moved up my list.. So am I correct in assuming that HMRC will end up whacking me for taxes for the full value of the HC even if it originated in the UK?
  16. Hello everyone, I was wondering if anyone has had something repaired/warrantied in the US. My situation: I discovered that my over ten-year old handpad has some display corruption and the battery is low. It needs a special battery with a pigtail and the vendor (AP) has advised that shipping the battery alone would incur a $120 "hazardous materials processing" charge if shipped - but this charge is not present if the battery is installed in equipment. They suggested I ship them the entire handpad, they replace the battery, reflash the firmware, etc. etc. and ship it back. They said this would cost less or about the same as the $120 charge alone, and I would not have to replace the battery myself (which is a very involved procedure). My concern is - will HMRC whack me for taxes? the handpad is a $1000 item so it would attract a $200 tax if ever. Anyone have any experience with AP gear sent to the US for repair?
  17. 2" unguided requires very large worm wheels. My Mach1 is about 2.8" unguided before PEC. The 28" figure for the Star Adventurer is very good considering its price and provenance. My old CGEM was about 32" so this tiny mount is actually marginally more accurate than my particular CGEM.
  18. Note that the 2" RMS is guided. The periodic error is around 28" p-p unguided.
  19. about 8 minutes, or a bit less than one worm period. however i don't see why this level of guiding cannot be maintained indefinitely, since the periodic error is quite regular.. note that i no longer have the Star Adventurer. I bought it for a lightweight portable mount, but it's too small for my 80mm refractor, so I'm using an EM11 now. Much much heavier to be sure, but still in the realm of airline transportable. And with GoTo.
  20. I use a used Gitzo G1340 Mk 2. 20lb rating. Roughly equivalent to a current GT 3-series. Damps vibration better than the heavier aluminium tripod from my Vixen Polaris, weighs 6.5 lb. A modern Gitzo carbon tripod would be half the weight.
  21. I bought a Sirui R2004 tripod for the Star Adventurer. This tripod is alleged to carry 15 kg or 33 lb. Note my use of the word "alleged." With an 80mm APM Lomo triplet, damping time at 120X is 8 seconds! I swapped the Vixen Polaris tripod, and damping time went down to 4 seconds. So - the Star Adventurer is too puny to carry the APM Lomo triplet, and the Sirui tripod makes things worse. http://orlygoingthirty.blogspot.sg/2014/09/sirui-r2004-tripod-for-astronomy.html
  22. The one that I wrote (link above) has been tested with INDI and works.
  23. i did a different approach - because I don't know how to program in Windows, i re-implemented the Lacey / Moonlite protocol - http://orlygoingthirty.blogspot.sg/2014/04/arduino-based-motor-focuser-controller.html works fine for me...
  24. I've said this before and I'll say it again... the accuracy of the polar scope in the Star Adventurer is pretty darn good. I was pleasantly surprised. It was better-aligned out of the box than my PASILL (Astro-Physics) polar scope.
  25. .. and the Star Adventurer can be guided, not something that the Polarie can do.
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